(1) Field of the Invention
This invention relates to a process for scale inhibition using random copolymers of acrylic acid and a co-monomer that is hydrophobic.
(2) Description of the Related Art
It is known to use low molecular weight ionic polymers and copolymers as scale inhibitors for cooling water towers and boilers in industry. Most commercially available polymers in the market today used for this application are based on carboxylic acid.
Copolymers of acrylic acid and monomers that have hydrophobic properties are well known, e.g. CARBOPOL® thickeners manufactured by B.F.Goodrich Co. Uses for these copolymers have been disclosed for a variety of applications. U.S. Pat. No. 5,118,435 discloses their use in anti-icing compositions, while U.S. Pat. No. 5,106,609 discloses their use as a vehicle in cosmetic compositions.
U.S. Pat. No. 4,833,179 describes the suspension polymerization of a pressure-sensitive acrylate copolymer bead containing a modifier moiety like 2-polystyrylethyl methacrylate macromonomer, which renders the copolymer bead non-agglomerating at room temperature and safely transportable. U.S. Pat. No. 5,294,693 discloses the use of an acrylic acid copolymer terminated by a fatty hydrophobic chain having at least 26 carbon atoms as a modifier of rheological properties, stabilizing agent, and suspension agent for coarse mineral or organic materials in various applications. Other known applications for these copolymers are as anti-soiling treatment for carpets and carpet yarn (U.S. Pat. No. 4,081,383) and photographic recording material (U.S. Pat. No. 5,134,061).
All citations referred to under this description of the “Related Art” and in the “Detailed Description of the Invention” are expressly incorporated by reference.